Department of Cell and Molecular Biology-Microbiology, Goteborg University, Goteborg, Sweden.
Department of Molecular Biotechnology, Chalmers University of Technology, Goteborg, Sweden.
Institut de Biochimie et de Genetiques Cellulaires du CNRS, Universite Victor Segalen, Bordeaux, France.
Carbonylated proteins were visualized in single cells of the budding yeast Saccharomyces cerevisiae, revealing that they accumulate with replicative age. Furthermore, carbonylated proteins were not inherited by daughter cells during cytokinesis. Mother cells of a yeast strain lacking the sir2 gene, a life-span determinant, failed to retain oxidatively damaged proteins during cytokinesis. These findings suggest that a genetically determined, Sir2p-dependent asymmetric inheritance of oxidatively damaged proteins may contribute to free-radical defense and the fitness of newborn cells.